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Interactive Signal & Noise Simulator Online


Interactive Signal & Noise Simulator

Theory: Waveforms, Noise, Variance, and SNR

This simulation generates a noisy periodic signal by combining a waveform with a noise component: 


x[n] = s[n] + w[n]

Where:

  • s[n] = the chosen signal (Sine, Rectangular, or Triangular)
  • A = peak amplitude of the waveform
  • f = frequency of the waveform
  • w[n] = additive noise (Gaussian, Uniform, Laplace, Binary, or Pink)

The variance (σ²) determines the noise power relative to the signal strength: 


σ² = P_signal / (10^(SNR_dB / 10))

The Signal-to-Noise Ratio (SNR) in decibels is calculated as: 


SNR_dB = 10 * log10(P_signal / σ²)

For these periodic signals with amplitude A, we approximate the average power as: 


P_signal ≈ A² / 2

These formulas allow for seamless conversion between noise variance and SNR, giving you precise control over the signal quality and interference levels.

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